Before 1996 this parasite was a curiosity. It was first described in people in 1979, and in the United States it was mostly a souvenir of travel. Then in the spring and summer of that year raspberries imported from Guatemala sickened roughly 1,465 people across twenty states, the District of Columbia and two Canadian provinces, and Cyclospora became a foodborne pathogen with a paper trail. That outbreak is the reason cyclosporiasis became a nationally notifiable disease in 1999. It is also, three decades later, still the template: an imported raw item that nobody cooks, a grower nobody in America has ever seen, and a case count that arrives long after the food is gone.

Here is the whole record on one page.

Read down the middle column and the first thing you notice is that there is no American farm on it. CDC has put that finding in print: for the subset of United States outbreaks documented from the mid-1990s through 2015 in which both the food vehicle and its source were identified, the implicated produce item had been imported. Guatemala, then Peru, then Mexico. Not one confirmed vehicle in thirty years was grown here.

The second thing you notice is what is missing. Nothing cooked, nothing canned and nothing frozen has ever been implicated in a United States Cyclospora outbreak. Every single vehicle on that list is a raw item that leaves the field and reaches a plate essentially unchanged: a berry, a leaf, a pod, a bag of shredded lettuce. There is no kill step anywhere in that chain, and there is no kill step available. FDA said so in its own environmental assessment of the 2013 outbreak, where halogen sanitizers including chlorine are described as not reliably killing this organism. Washing produce is good advice for other reasons. It is not a defense against this one.

The third thing is the migration. Guatemala owned the 1990s and turned up again with snow peas in 2004. Peru supplied the mesclun in 1997 and the basil in 2005. Since 2013 it has been Mexico, without interruption. And the American response each time has been an import alert on the last thing that made people sick. FDA began detaining cilantro from Puebla in April 2015, and domestic cilantro-linked illness did fall. The outbreaks came back as basil in 2019, as bagged salad in 2020, as a salad kit in Florida in 2021 and 2022, as parsley in a closed federal file in 2025, and as shredded iceberg this summer. Chasing the commodity has never once addressed the water.

One name appears on the list twice. Taylor Farms de Mexico supplied the salad mix behind the Iowa and Nebraska illnesses in 2013, out of Guanajuato, and it supplied the shredded iceberg behind the fifteen-state outbreak in 2026, out of central Mexico. In August 2013 the company suspended production and resumed later that month with FDA concurrence, on a stated commitment to a comprehensive sampling program covering its products and its water. Nobody has ever published what that program found, or whether it is still running. That question is thirteen years old and it is the same question this summer.

Now the scale, and this is the part that should stop anyone who works in this field. CDC has recorded outbreaks in its National Outbreak Reporting System since 1990. Across those thirty-three years the system holds 181 Cyclospora outbreak records totaling 6,251 illnesses and 198 hospitalizations. The federal count for this one outbreak, as of this week, is 6,358 illnesses, 278 hospitalizations and two deaths in fifteen states. A single summer has passed the entire recorded history of the disease in the United States, on the government’s own narrow definition, in illnesses and by a wide margin in hospitalizations. And the government’s definition is the small number. The fifty state health departments, added up, report more than 25,000 people sick, and Michigan alone reports 12,485 with 279 hospitalized.

The honest caveat travels with that comparison, because I would rather say it than have it said to me. Reported case counts for this parasite track testing practice as much as they track illness. The first FDA-cleared multiplex stool panel carrying a Cyclospora target arrived in 2014, and by 2019 most large clinical laboratories had one. That is a large part of why 2018 and 2019 look so different from 2005. Comparing 2026 to 1996 is comparing a year when doctors can find this thing to a year when they mostly could not. That cuts both ways, because the older numbers are the ones that were undercounted, and CDC’s own burden model still assumes about eighty-three actual illnesses for every laboratory-confirmed case.

What has not changed across the whole table is the absence of any regulatory standard. There is no limit for Cyclospora in irrigation water and no limit on produce. There is no validated intervention. There is no genotyping result published for this outbreak, though CDC has had the tool since 2018. A grower in perfect compliance with every rule that applies to it is doing nothing whatsoever about this organism, and has not been for thirty years.

What has changed is the counting. FoodNet dropped Cyclospora from federal surveillance effective July 1, 2025, ten months before the first illness in this outbreak. And there is a smaller thing worth recording, because it made this compilation harder to assemble than it should have been. CDC’s own outbreaks page describes itself as a selected list of active and past outbreaks. As of today, it lists exactly one: the current one. Every outbreak in the table above had to be reconstructed from MMWR, from archived press releases, from an FDA commissioner’s statement in 2018 and from the trade press. The agency that investigated all of them is no longer displaying them together.

That is the case for keeping the list. Thirty years, one route of transmission, one category of food, three countries, no kill step and no standard, and a number that has now increased by an order of magnitude. Each of these outbreaks was treated as a discrete event with a discrete recall, and each recall reached forward from the day somebody noticed, which is always after the people who got sick first had already eaten the evidence. Put end to end they stop looking like accidents and start looking like a system operating exactly as designed. The 1996 raspberries produced a notifiable disease. It is worth asking, before this season closes on August 31, what 2026 is going to produce.